[Interpreter] Add support for for..in.

src/interpreter/interpreter.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/interpreter/interpreter.h"
 
 #include "src/code-factory.h"
 #include "src/compiler.h"
 #include "src/compiler/interpreter-assembler.h"
 #include "src/factory.h"
@@ skipping 1053 matching lines @@
 
 
 // Return
 //
 // Return the value in the accumulator.
 void Interpreter::DoReturn(compiler::InterpreterAssembler* assembler) {
   __ Return();
 }
 
 
+// ForInPrepare
+//
+// Returns state for for..in loop execution based on the JSObject in
+// the accumulator.
+void Interpreter::DoForInPrepare(compiler::InterpreterAssembler* assembler) {
+  Node* js_object = __ GetAccumulator();
+  Node* result = __ CallRuntime(Runtime::kInterpreterForInPrepare, js_object);
+  __ SetAccumulator(result);
+  __ Dispatch();
+}
+
+
+// ForInNext <for_in_prepared>

[rmcilroy, 2015/10/26 14:04:01]

/s/for_in_prepared/for_in_state

[oth, 2015/10/28 11:53:12]

Done.

+//
+// Returns the next key in a for..in loop. The accumulator contains the current
+// zero-based iteration count and <for_in_prepared> is the state returned by
+// earlier
+// invocation of ForInPrepare.

[rmcilroy, 2015/10/26 14:04:01]

remove extra newline

[oth, 2015/10/28 11:53:12]

Done.

+void Interpreter::DoForInNext(compiler::InterpreterAssembler* assembler) {
+  Node* index = __ GetAccumulator();
+  Node* for_in_state_reg = __ BytecodeOperandReg8(0);
+  Node* for_in_state = __ LoadRegister(for_in_state_reg);
+  Node* receiver = __ LoadFixedArrayElement(for_in_state, 0);
+  Node* cache_array = __ LoadFixedArrayElement(for_in_state, 1);
+  Node* cache_type = __ LoadFixedArrayElement(for_in_state, 2);
+  Node* result = __ CallRuntime(Runtime::kForInNext, receiver, cache_array,
+                                cache_type, index);
+  __ SetAccumulator(result);
+  __ Dispatch();
+}
+
+
+// ForInDone <for_in_prepared>
+//
+// Returns the next key in a for..in loop. The accumulator contains the current
+// zero-based iteration count and <for_in_prepared> is the state returned by
+// earlier
+// invocation of ForInPrepare.

[rmcilroy, 2015/10/26 14:04:01]

ditto

[oth, 2015/10/28 11:53:12]

Done.

+void Interpreter::DoForInDone(compiler::InterpreterAssembler* assembler) {
+  Node* index = __ GetAccumulator();
+  Node* for_in_state_reg = __ BytecodeOperandReg8(0);
+  Node* for_in_state = __ LoadRegister(for_in_state_reg);
+  Node* cache_length = __ LoadFixedArrayElement(for_in_state, 3);
+  Node* result = __ CallRuntime(Runtime::kForInDone, index, cache_length);
+  __ SetAccumulator(result);
+  __ Dispatch();
+}
+
+
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8